The present invention relates to an apparatus for and a method of securing fastners, and more particularly an apparatus and a method of tightening a tapped member on a work with a predetermined torque.
An example of tightening a tapped member, such as a tapped nut, on a work is found in manufacturing power steering gear assemblies for automobiles.
Referring to FIG. 11(a), an automotive power steering gear assembly is described. It comprises a gear housing 1 with an integral power cylinder 2, and curved pipes 3. Mounted within the gear housing 1 are a gear train of the rack and pinion type and a rotary valve. The curved pipes 3, which are formed by bending straight pipes, interconnect the gear housing 1 and the power cylinder 2 and serve as hydraulic fluid passages. It is the conventional practice in manufacturing the gear assembly to manually assemble the curved pipes with the gear housing integral with the power cylinder by tightening flare nuts mounted on the curved pipes on their end portions to a predetermined torque.
An object of the present invention is to provide an apparatus for and a method of tightening a tapped member automatically without any labour.